Thermodynamic motor.



5 SHEETS-SHEET 1.

' "lar 4 Patented Nov. 15, 1910.

P. K STERN. I'EEBMODYNAMIG4 MOTOR. APPLIOATIOH FILED NOV. 19, 1000.

P. K. STERN. THBRMQDYNAMIO MOTOR. LPPLIOATIOI FILED-NOV. 19, 1900.

Patented Nov.*15, 1910.

- 5 SHEETS-snm 2.

P. K. STERN. 4THERMODYNAMIC MOTOR.

APPLICATION FILED NOV. 19, 1900.

Patented Nov. 15, 1910.

lo Fig] Snom hoz I?. K. STERN. r i THERMODYNAMIC MOTOR. AAPPLIoA'rIoNHum Nov. 19, 1900.

Patented Nov.15, 1910.

5 SHEETS-SHEET 4.

P. K. STERN.

THERMODYNAMIG MOTOR.

LPPLIoATIoN FILED Nov. 19, 1900.

Patented Nov. 15, 1910.

5 SHEETS-SHEET 5.

`UNITED sTATE's PATENT OFFICE.

.PHILIP z. sTEnN, or New 'Yom-x, N. r. i

THERMODYNAMIQ MOTOR. u l* Specification of Letters Patent. Patented Nov,15, 1910,

epilation mea November 1s, moo. sem-1 in. 36,993.

To all whom may concern:

Be it known that I, PHILIP .K. STERN, a

citizen of the United States, residing at the city of New York, inthecounty of New York and State of New Xork, have invented f as a fuel forsupplying the energy for op eratin the en ne 1n a manner where when itis employed to perform the mechanical work of t e engine by theexpansive property it possesses when confined, due to its.

sensible heat, it is also used to further perform the mechanical work bythe expansion due to the heat of chemical combination by combustion.

My invention has, therefore, reference to a thermodynamic motorembodying both that class of heat engines known as expansive engines andthat class commercial] known as ex losive engines, and inasmuc as thatthe uel employed'in explosive engines utilizes the heat of chemicalcombination to perform the mechanical work of the engine, and theso-called expansive engines, usually steam or va 'or engines, erformtheir mechanical wo;` by the sensi le heat contained in the vapor, Iprefer to distinguish lthe two classes of engines by the` usualcommercial method of expression.

terming the steam or vapor engine an expensive engine', and the ordinarycommercial gas engine an explosive engine,^a1thou h both types of engineare operated .by t e expansive property of the power medium. I mean bypower medium either a carrier of energy' in the form of vapor, which,when' suiiiciently heated urnishesthe necessary energy for operating theengine, infwhich case the power me ium givsu its energy to the piston ofthe engineand yvirtuefjof its expansive property transfor'ms thesensible heat ofvthe'vapor into mechanical work,

' or a producer of energy in the' form of some combustible volatileliquid' which when `heated Vby its chemical'- combination "with anotheringredient becomes a power medium, in which case the said vapor istransformed in a powermedium by' virtue of the expansive property of theheated gases con tamed in t e chemical combination.

With this method of interpretation, my

'invention relates then, to a new class of heat engines or thermodynamicmotors, wherein the power medium is used both expansively andexplosively.

As my` invention relates to the transf formation of the kinetic ener ofa power medium by both the direct an the indirect methods of utilizingthe potential ener of the fuel to this end, I have' referre to designatethe combination o these two methods when employed in the operation of amotive power apparatus, a thermodynamic motor.

in heat engines of the explosive type which havecome to my notice, therefrigeratlon necessary in consequence of the excessive heat developedby the combustion' would have been usein lieu of the refrig` eratingliquid fore ling the cylinder, 1s used for taking upthe heat of therefrigerating liquid. In any of these methods, however, the heat carriedoli` by the waterjacket or radiating surfaces dissipates and wastesabout forty per cent. of the heat' available vfor l'performingthemechanical workfof'th'e engine. vrIn thermodynamic,transformation ofthe. secondorder, i, e., iwhere heat is communicated, to a power..medium 'such as water or other volatile liquids and the 'heat of .thelvvapor taken, up by the motor in thepertormance of mechanical work,there is a con siderablev leakazegas it were, yor more propf erlystated,1a dissipation of a large centrage of the .heat-'units which isnoltmmade available in the process of evaporation and bv the developmentof mechanical .work by the expansion of a liquid into a vapor, there isbut a fraction of the heat ofthe fuel con:

ioo

sumed in the vapor generator transformed into mechanical work of theengine.

As a counter distinction between the indirect process or that justmentioned and the direct process, or that wherein the combustion of thefuel develo s by the expansive force of the chemical) combination of thegases within the cylinder of the motor, a motive power -which impels theiston against the resistance of it load, I sha 1 designate the motoroperated by the indirect process an expansion engine and the recesswhich the heated power medium Vun ergoes the expansive process while thedirect process of transforming the heat into mechanical motion, I shallterm an explosive process and the engine developin work through Such aprocess will be referred to hereinafter as an vexplosive engine. It iswell known in the art that the dissipation o'f heat in developingmechanical work by the expansive process of a power medium is much moreexcessive than when the mechanical work is developed by the explosiveprocess of the combustibles.

It is the object of my invention to so construct a thermodynamic motoras to combine these two methods of transforming heat into mechanicalwork, so that the heat of the explosive type of heat engine, which i'snot all available in ractice, may in part be applied so as to per ormmechanical work by the expansive process, and by this method of blendingthe two distinct rocesses of transforming `heat into meehanlcal work inthe operation of one machine, the vapor generator for the expansiveengine and the 'cooling-jacket for the explosive engine are combined,and these two distinctive methods,

which have heretofore been separate and independent adjuncts to thedevelopmentl of motive' power, are so combined in one thermodynamicmotor by my invention, as to provide for the one, by the other, whateither 1s lacking. The manner in which I have carried out my inventionto this end is to construct a thermodynamic motor dually, whereby theexpansion portion takes up 'energy from the explosion portion, and theexplosive portion takes up energy from the expansion portion, inthermodynamic transformation, and in a manner so as to interchange whatwould be when considered independently the respective heat losses ofeach section from one portion to another so as to be turned into usefulwork atthe crank-shaft of the thermodynamic motor.

I have given preference to the use of avapor of an inflammable liquidrather than to the evaporation of water for the power medium, for thereason that when it is used expansively to develop work by the sensibleheat which it contains when heated by the heat due to combustion in theex losive aor-l tion, it may beused as an ingre ient o -the explosivemixture in the cylinder of the explosive portion. This might be accom-`plished by employin water and evaporatlng it into steam, an then usingthe steam in a su erheated state as an ingredient of the exp osivemixture, but ns steam would not be as volatile as some of the forms ofhydrocarbon, and therefore would not. relieve the explosive cylindersulieiently of its exeessive heat, as well as not bein" capable, initself, of furnishing fuel for tie ex )lesive mixture, I have givenpreference to a liydrocarbon liquid fuel for operating my iinproved heatengine. After the vapor has given up its energy to the working` pistonand is4 then exhausted, a considerable amount of heat is carried off bythe exhaust, which, being at a lower pressure than that which can beutilized in the transformation of heatinto mechanical work, is thrownout into the atmosphere or into a condenser and dissipated, just as thesurplus heat generated by the combustion of the explosive mixture in thecylinder of an explosive cno'ine is carriedoti by the water-jacket. orradiating surfaces depending from the cylinder ofthe engine.

In constructing a thermodynamic motor according to my invention, theexhaust from the expansive portion 1s taken into the cylinder of theexplosive portion and the lient contained in the exhaust vapor isutilized in increasing the activity of chemical combination of the gasesemplo ed in the explosive process, and, reciprocal y, the surplusI heatwhich is developed in the cylinder of thc explosive portion istransmitted to the liquid, thence to the cylinder of the expansiveportion. Thus by this interchange, the heat whch would otherwise havebeen wasted is employed usefully. I consider this feature a distinctadvance in the application of thermodynamics to motive power development, and of considerable advantage to the art to which my inventionpertains.

Another object of my invention is to provide a means of more completelyclearing the cylinder of the explosive portion of the products ofcombustion than has been attained in the older forms of gas engines andthose in vogue at the present time and previous to -my invention.

Another object of my invention is to provide a means for increasingthe'eiiciency of 'the explosive ortion by increasing the coinression oft e mixture prior to ignition.

his feature of iny invention I accomplish by the provision of a mixtureweak in atmosphericy air and raising its temperature by compressionuntilit may be as readily ignited as mixtures rich 1n atmospheric airl at alower compression.

The different feitures of my invention are fully illustrate f'in thedrawings and described clearly inthe subject' matter of thespecification, and finally more particularly pointed out in the claims.

In the drawings in which I have illustrated the different features of myinvention, I have preferred to describe a vertical or upright form ofthermodynamic motor 4combining the` expansive and explosive methods ofoperation, by means of a singleacting single-cylinder expansive type ofheat engine, and what is known as la two-cycle explosive gas engine,constructed according to my invention in the aforesaid manner is shownin the drawings, of which- Figure 1 is a vertical sectional view takenon the line X X of Fig. 2. In this view I have so disposed the parts asto show the entire construction of the motor and all of its details,though in practice the position of the different valves shown may beconsiderably varied for the sake of convenience. Fig. 2 is a top planview of my improved thermodynamic motor, looking down upon the cylinderheads and vapor chests.' Fig. 3 is a horizontal sectional view taken onthe line 3 3 of Fig. l, so as to show the vapor chest of the expansiveportion, the top portions of the vapor chest, and the other Workingparts which are inclosed in the upper part of the motor. Fig. 4 is atransverse sectional view taken from Fig. 1 on the line 4 4, so as toshow the passage ways and ports more clearly; those which I have shownin Fig. l, where they are not taken in section, by dotted lines, areillustrated in this ligure. Fig. 5 is a transverse section taken on theline 5 5 of Fig. l, showing the tempering flues of the explosiveportion, the vapor jacket of the expansive portion, and the exhaustconnections of both the ex ansive and explosive portions. transversesection taken on the line 6 6 of Fig. 1, to more clearly illustrate theexhaust drum. Fig. 7 represents a cross-section of the vapor-chest and aportion of the small expansive cylinder and vapor-jacket. Fig. 8 is aside elevation of my improved thermodynamic motor, looking at the end ofthe crank-shaft so as to show the angle of centers of theconnecting-rods and the different working parts of the motor fromthatpoint of view. Fig. 9 is a front elevation of the motor, showing asection of the air and vapor mixer and scavengering valve, and thepipe-connections and valves of the motor from that point of view.

The explosive side of the motor is that to the -right ,of the line-9 9i`n Fig. 1,the expansive side being to the left of this line.

In order to designate similar parts I eml s out the several views.

The cylinder A is cast integral' with an enlarged or trunked extension Asons to form a secondcylinder.

Fig. 6 1s a- I have shown incylinder A and the cylinder B of about oneto nine. That is to say, the small cylinder A has a cross-section ofabout one-ninth of the cross-section'of the explosive cylinder B, thatis, one-third of the diameter. The 0bject in this diminution in the'size of the expansive section is to obtain the'greatest economycommensurate with the efficiency of the expansive and explosivecombination at that vapor pressure which it is considered most practicalto employ for operating the motor and burning up the exhaust of theexpansive cylinder in the explosive cylinder. This pressure must be theresult of the proper adjustment of the conditions which depend upon (l)t-lie physical properties ofthe liquid tbe evaporated, (2)v the rate atwhich the small piston will be turning the heat of the vapor, which isreceived from the products of combustion of the explosive port-ionthrough the cooling-jacket, into mechanical work, (3) the quantity ofinflammable vapor rejected after expansion to be used in the explosivecylinder, (4) the practical limit of expansion for the vapor, and (Fythe limit to which the vapor can be heated in the cooling-.jacket so asnot to have too high `a temperature for the explosive cylinder.

The vapor capacity of the expansive cylinder is determined, then, bythese considerations, which establishes a proportion between the twocylinders in their respective capacities of about one to nine, asalready stated.

Within the cylinder A a. piston a of the plunger type is employed tooperate the connecting-rod l in the usual manner fory single-actinfrengines, so as to drive the crankshaft C lby the crank C. The plunger orpiston 'a has-an enlarged or trunked end a, which, when working in thecylinder A', is arranged so as to form, together with the cylinder A andcheck valve 2, an exhaustpump for scavengering the residual of theproducts of. combustion left in the cylinder B after exhaustion. Thecheck-valve 2 is employed to open the outlet for the air contained inthe cylinderAA when the piston a is descending, and which closes whenthe piston a is ascending. Another check-valve 2, shownin Figs. 5 and 9,is secured to the exhaust outlet 9 of the exhaust-drum 9, and isconnected up with the check valve 10 by a pipe 93, so as to relieve thecompression of the atmosphere or gas within the clearance space betweenthe top of the pist-on a and theA adjacent end\of t-he cylinder A whichtakes' place when the piston a is ascending.

It will be 'well here to state prior to a general understanding of thedetails of the motor, that the construction is such as to p'rovide for'the two cycle explosive portion of izo the motor, a means for.preventingV the escape A the drawings a proportion between the small ltwo cycle motors of this character when the o fuel is bein@r transferredfrom the crank chamber to tie combustion chamber during a downwardmovement of the piston. Provision is also made against the forcing ofthe fuel from the combustion chamber out o f the exhaust at the initialof the compression stroke.

In order to accomplish the effectual reservation of the fuel to theconfines of the combustion chamber, I have arranged controlling valveswhich operate in a manner to effeet a reduction of the pressure of thegases in the combustion chamber whereby the same shall be less thanatmospheric pressure when the piston B is in any of the positions toelTect a register-of the por-t 9 with the port 8 or lO either onraninward compression or an outward working stroke and to this end I havearranged the said valves 4in a manner whereby they will be opened duringthe operation of the motor against an adjustable and variableresistanceV and which resistance is adjusted tobalance the requiredpressure for. the combustion chamber. The

' expedients preventing the escape of the fuel in this manner and theirfunction will be more particularly referred to in the followindescription relative thereto.

'he va or-chest D having the usual piston-valve admission ports 3,manvaporspace 4 and 4', inlet ports 5, exhaust-space 6 and exhaust port 6,is employed to control the ex anslve vapor which impels the piston aownward 1n its working stroke. The piston-valve D is movedby the ordi-'nary well-known valve-gear controlled by a shaft-governor, whichregulates the lap and lead of the valve by the speed of the crankshaft.This valve-gear also serves to operate the tappet-rod P, which carriesthe various tappets, which will be explained hereinafter, for operatingthe fuel control and air valves and ignition plu of the explosive enine. The tappet-rod is ri idly connected y a bracket or arm I to t estem of the valve D. In the character of-governor referred to theeccentric on the crank-shaft which' drives the valve-rod, is shifted bya Weight, upon variations taking place in the speed of the crank-shaftso as to alter both the lap andthe lead of the slide-valve. Astheseovernors are so well-known in the art, I ave considered it unnecessaryto show any special construction inthe drawin and consequently haveomitted the detais from the different views.

The cylinder A is surrounded by a jacket A2 which serves the pur ose ofboth a dryva orv drum for furnis ing vapor tothe cy inder A. through thevapor-chest D and valve D, and also a means to prevent the loss of thesensible heat of the working vapor by condensation. In order to separatethe dry vapor from that in which condensation is liable to take place, Icast or otherto run from the head end downward almost the full length ofthe jacket, thus dividing it into two sections ais and a* .after theInanner of a steam separator.

E is a three-way cock adapted to register with the vapor-space 4 by aport 7, and with the neck d of the piston-valve D by a port 7. The cockbeing in the position shown in Fig. l, the vapor is about to enter fromthe vapor-space 4 through the ports 7 and 7 into the small cylinder A bythe port 5 around the neck d of the valve D. When the cock E is turnedin a direction so as to register with the ports 7, and 8, communicationwill be established with the cylinder B by the pipe F. The object ofthis threeway cock 1s to admit of the turning on of the vapor to eitherone of the cylinders A or B at will, so that in starting up the engine,vapor may be turned on so as to enter that cyinder avin its piston,connecting-rod and crank off rom the line of dead center. The exhaustort 6 and the exhaust space 6 are connecte by a lateral extension of theport 6, that is to say the said port follows the contour of the valveD', as shown more clearly in Fig. 3. The exhaust space 6 hascommunication by means of a pi e V with a vapor check-valve V (shown 1nFigs. Q, 7 and 9) located on the cylinder-head G' and from the deliveryof the check-valve the exhaust vapor passes through an indexedhand-controlled valve V, thence through an elbow, to amixer V Where itis mixed with atmospheric air, the mixture then bein carried by a pipe Uthrough a checkva ve V* (shown in Figs. 6, 8 and 9) into the crank-boxchamber N N2 of the crank-box4 N N so as to enablethe explosive mixtureto enter underneath the piston B of the explosive portionrfA port 9cored or otherwise formed in thelpiston B so as to re ster withf theexhaust port 8 of the exhaustrum 9 and the scavenger port 10,is..brougl1t into communication with these ports 'alternately when thepiston Bhas about completed its outward stroke. The exhaust-drum 9 iscored or otherwise formed in the body of the cylinder B and has anexhaustoutlet 9, shown in Fig. l5. The port 6 formed in the piston B isadapted to admit the explosive mixture from the crank-box chamber N N tothe upper end of the cylinder B by way of port 6 connecting-pipe fv,back-pressure check-valve lv- (shown in Fig. 5) and perforated plate Jwhen the port 6 of the iston B shall register with the port 6. he port 6is to one side of the port 8 or 10, so that when the piston B is inmotion, the

port 6 will not register with any of the 'is clearly shown in Figs. 5;and G. By

arrangement of the port'I 6 'with' 'respect to the ports 8 sind 10, thefuel under emressio'n in the crankb'on chamber N2 N by te downwardmoven'icnt of thepiston B will find its escape only through. the port 6.

The mixer V is more clearly illustrated in Figs. 2 and 9, and thedisposition fof the puppet air intake valve fv" and itsreturn springs 8ands" as the piston- B is making its inward or compression stroke isalso shown in these figures. To adjust the tensionA of these sprin s soas to enable the valve 'v" to operate wit the action of vthe piston Bwhen it is making its inward stroke, and is inducting the charge'through the valve fu into the crank box chamber N N2, I arrange a milledhead nut n threaded upon the stem n of the puppet intake valve c. Thetwo compressprings s and s" are arranged so' as' to operate together toreturn the valve la to its seait. Interposed between the-'two springs .9and s" is a pivoted lever f pierced so as to admit the passage of thevalve-stem n through it. The arrangement of this lever is such that uponmoving in a .direction the lighter spring s" will take up the thrustfor1 seating the valve o. During' a long stroke of the tappetirod P such`as would be imparted to it by the action of the governor dii-ring adiminution in .the rotational' speed of the engine, Athe tappet t, whichis secured with-a set screw to the tappet-rod P will inipinge againstthe lever f as the valve D travels backward or to the right of itspositionshown in Fig. 1; and by virtue of the tappet t' and lever fcompressing thev stili'er spiral spring s, and' leaving only the weakerspring' s to seat the intake valve fv, the intake of the atmospheric airinto the valvey will be admitted more freely' than when the valveD isdecreasing its stroke wheeby the shorter ath' of' action is given tothe-tappetrod Tiat is to say,;,w henthe lap of the valve D has beendecreased. The extent to which the stiffer spring-fis is compressed' bythe lever f, therefore depends upon the lap and lead of the valve D. Asthe oint of cut-oi of -the vapor to the small ,cylinder A is alsoeiiected by the valve travel, the quantity of vapor exhausted into theexhaust space 6 and into the mixer is varied according yto the load,that is, according to the speed Vof the crank-shaft; consequently thesame ratio, though the total quantityv of a-ir and vapor, (that is, theexplosive mixture,) taken' into the crank-'box chamber N N2. anddelivered vinto the' Cylinder' B bel hind the piston B" in ai manner as"alre'..dy

stated, is varied. For the niaii'i adjustments more or less suction bytrolle'd exhaust va* orlvali're Y and the in# dexeilhand-contro led airvalve V are shown with their stems in a horizontal "osition in thedrawings for convenience of 1 ustrati'on.

In practice, however, I prefer to' place these ,valves so that theirstems will stand in a i* position so as to avoid the displacement of ilthe adjustment of the valves in consequence of vibration during theoperation of the engine. Thetempering iues, 11, which are in thisexample eight in number, are formed in the casting of the cylinder B anddisposed circumfercn-tia-lly about the same, as shown in Fig. 5', andregister with an annular groove or channel 11', cast in the cylinderheadG. The cylinder-head G, which' is f adapteitl to; cover the head ends ofthe cylinders A and' B and contains those parts'o'fthe mot-or locatedabove the line' 4f i orf Fi' 1 isf al casting' carrying thevapor-'chest' an a'l off the mechanism which is shown above this line'.The manner of securing the head G' to -the cylinders more clearly shownin top i plan View Fig'. 2 and also in Figs. 3 and 4. so astocoi'nfpress'A the springs, the tension of C'Oim-icaiiiifg Wit'h tll'lannular 11"' are the ventilat'ing' passages 12, which -comfmunicatealso' with the smoke-fine i3 and three-way cock A burner' or heater Hsuch asis used in ordinary gasolene or las stoves, is disposed about theexterior of the' cylinder B and is so arranged as to have its jets" r'e'ster with the temperin ilues 11, as shown' in Fig'. 1. The dispositionof the tempering-nues l1 and the heater H rs such as to` transmit heatto the jacket I so as to` he'at whatever' liquid may be' containedthereiii. When the three-Way cock I-I has its valve k: turned into aposition sothat the port H registers with thel smoke flue 13, burnedgases will" pass 11p-through the tempering fluesilli into the annulargroove 11', Ventilating'l passageslf2, smoke-flue 13, lport H of thevalve It oE' the three-way coc H and intothe atmosphere. A i

-Formed the cylinder-head G is the scavengeri'ng air-sliowering device,which consists ,of a platev J having a multiplicity of smallperforations 14, as shown in section in Fig. 1 and in top plan view inFig. 4. These` perforations are so grouped as to Spread the air which istaken in throughthem as to form one continuous air piston when the airis taken in through the cylinder B, which will be explained hereinafter;the disposition of theseperforatiom will he in the' meanwhile moreclearly` understood by reference' toi'F-'igfs' 1" and 4., Communieatingwith the sina11` percrafioisj 14 ifs an annular air passa y, which is'formed in the eyinder' hea G; This is connecte-d with the atmosphere bya passage-way 15,

IBO

` the cross-head b .under a light pressure,

pression on the springs ,The valve-stem b is may be varied accordingscavengering intake check-valve 16 air supply pipe 17 and three-way cockthe arrangement-being such that when the threeway cock H has its valve hturned into that position shown Ain Fig. l,lthe .ingress to the cylinderB will be from the surrounding atmosphere into the port H of thethree-Wa cock H, pipe 17 scavenger intake checkvalve 16, passage-way 15,annular air passage J', and perforated outlets 14.

The scavengering intake cheek-valve 16 has a tubular frame-work which isslotted or cut away so as to admit of the introduction of the arm f ofthe bell-crank lever f f, which also forms a guide-way for thecross-head b". The check of the valve 16 is held on its s eat by theadjustable compression springs b and b acting on the valvestem b by afixed collar on the stem b and against the underneath side of theadjustable sliding cross-head b" which takes the .upward thrust of thesprings and is adjusted i by a nut threaded to t i Figs. 1 and 9, thearrangement being such e stem b as shown in that upon turiiiii the nutin one direction, is forced down so as to create a comparatively greaterpressure, thereby preventing the valve from opening and upon turningdirection, the comwill be released so as to allow the valve to o en moreeasily.

assed through a pei'- 'orationin the arm f of the aforesaid bellcranklever, so that the arm f shall be interposed between the two sprin s,the upper sti er s ring b and the weaker ower spring the n ut in theopposite n l b an the othei arm f 1s arranged so as to stand in anapproximately vertical position,wherebv it is adapted to contact withthe ta pet T secured to the tappet-rod l when t e latter is re ioved bythe valve-gear toward the left ofhatposition shown in Figs` l" and 9, soas to relieve the stiffness of the action of l:the springs b and. b.This variation in the stiiness of the valve by the action oft/he springsis due to climi-- nating, for the time being, the compression of thesti'l'er spring b and allowing the lighter spring b ne to keep the valveseated, after the manner as explainedpreviolisly iii connection with theoperation of the air intake valve 'v, whereby the atmospheric pressurecombustion chamber B resulting from the scavengering of the products ofcombustion therefrom by the suction of the piston a to the variation intension of the springs b and of the valve 16 in accordance with theaction' of the tappet-bar l). sufficient tension sliouldat all times begiven to the valve 16 irrespective of the re uired ,-throttling effectfor the motor to maintain the air pressure in the combustion chamber.approaching atmospheric the slide-valve D',

of the air contained in the` Itis necessary however, that' B prior tothe transfer of the fuel from 'its crank chamber to an extentconsiderably below that of the atmosphere.

Whcn the engine is in o eration so that the slide-valve D has consierable la that is sa when the speed of the cranlE-shaft y .is re ucedbelow the normal working speed,

the action of the governor will be to increase the stroke of the valve Dby shifting the eccentric on the crank-shaft farther from the'centeruplon which it rotates, and the.

ta pet 'l Wi by contact with the arm f re ieve the spring com )ressionfrom the valve 16 so as to allow t is valve to admit the incoming airunder a lesser pressure so that the air taken into the cylinder B willbe at ahigher pressure, that is, more clearly ressure, than when morepressure is required to o erate the valve. lhe effect of this is to filthe cylinder B with a volume of air more nearly at atmospheric pressurethan when the valve D is making a shorter stroke.

It will be observed then that the effect of the governor is not only toregulate the qnantity of vapor used in operating the expansive portionof the motor, which quantity, after beine` rejected from the cylinder Aasses out olf/the exhaust, after which it is urther employed as the fuelfor operating the explosive portion, but the quantity of air which isfinally mixed with the fuel and taken into the cylinder and compressedby the inward compression stroke of the piston B is also controlled bythe governor, and though the motor may be working on variable loads, therelative proportion of hydrocarbon to air in the ex )losive mixture maybe maintained on all loads, but the quantity of explosive mixture usedin o erating the explosive portion is varied. '1 ierefore the governorcontrols both the expansive and explosive portions of the motor inpractically the same manner. That is to say, the mean effective pressureof both the expansive and the ex losive portions of the motor is variedby tie lap and lead of without deteriorating the caloriic value of theexplosive combination by changing the proportion of the ingredients ofthe ex losive portion, which would be the efect if the quantity of fuelalone was varied. It will also be noticed that the time of ignition isvaried by the action of the governor as well,l and the adjustment of thetalppct t (see Fig. 2) by its set screw, and t e tappet-rod P must besuchas to give a later i7gnition on, light loads and anearlier'ignitioii on heavy loads, in order to maintain a constant speedand at the same time operate the motor economically. -To ascertain themanner in which the different valves should be properly adjusted so asto produce a proper fuel consumption for the motor, commensurate withthe work that the engine is performing, 'the different adjustments forthe springs on the lntake valves, the vapor exhaust valves and thethrottle-valve M, must be manipulated the head-jacket I, which isdisposed about the cylinder-head, as shown in'Fig. 1 in section, bymeans of a passage-way 18 formedin the castings. Within the head-jacketI is a float O adapted to control the amount of liquid fed to thejackets I and I by way of the cock K and feed-pump L. A port 9 formed inthe walls of the vapor chest D, shown in Figs. 3, 4.- and 7, establishescommunication between the jacket I of the cylinder-head and the sectiona4 of the vaporjacket A2 surrounding the cylinder A. The vapor-space 4of the vapor-'chest D has communication with the section a of thevaporjacket A through a port 20. Each of the ports 19 and 20 has avertical and a horizontal limb. The communicating passages which I havejust described are shown in section in Figs. 3 and 7 and in plan in Fig.

4. The port 20 has a throttle-valve M (see Figf) for controlling thesupply r-of vapor 'to the vapor-space 4- of the vapor-chest D.

The crank-box N N is divided into two -sections by a partition N2. Thepartition N2 the usual manner fo lubricating the crankpins of small engis. The lubrication is also carried up into the pistons in this Way andlthelubrication thus afforded haswbeen proven to be all that is necessaryfor both pistons and cross-heads for small-sized en-A gines of thedouble-cylinder, single-acting I plunger type in use. at the presenttime.

soA

`To start the motor running, assuming that the space in the cylinder Babove the piston B is filled with atmospheric air, the valve 71. of thethree-.way cock H must be turned intor a position as to establishco1nmunication with the tempering flues 11 for the burner H; this willbring the port II' farther to the left than when in the position shownin Fig. 1. The liquid fuel for oper# ating the engine is introducedthrough an inlet 21=provided` with a plug. The fuel I prefer to use forthis purpose is commercial naphtha having a speciiie gravity o f about.7696, containingabout of carbon. 18% of hydrogen and 10% of oxygen.This is commonly known as 'stove gasolenc. The

naphtba burner is turned` on and ignited, and after a sufficient amount'of .heat has been imparted to the naphtha in the jacket I, through thetempering fides 11, the ina htha will have become vaporized so t 'atwhen it has a pressure of about or 90 lbs. 'per square inch, asindicated by a pres- .sare gage connected up to the vapor-chest D butnot shown in the drawings, suicient pressure will be found in the vaporto start the engine up expansively upon manipulating the three-way cockE so as to i cause the vapor to act on the piston a, or on the piston Bthrough the pipe F, laccording to which one of the cranks C or C2 is offof the line of dead center. In order to eliminate the volume of the pipeF which -.would create excessive clearance for the cylinder B, acheck-valve 1, shown in Fig. 8, is introduced in the pipe F at a pointwhere it enters the cylinder so as to admit of the increase of the va)or from the pipe .F into the cylinder. A ter the motor has been turnedover sufficiently by the expansive property of the vapor the naphthabummer H may be turned ofi and also the threeway cock E, whereupon thethrottle-Valve M is turned on solas to admit vapor into the Vapor-space4. of the vapor-chest D which will venable the engine to be o erated bythe small expansive cylinder A iiaving its vapor admitted and cut off bythe travel of the piston-valve D according tothe speed of thecrank-shaft C, as in an ordinary single-acting steam engine with a shaftgovernor. As the small piston a is moving downward the piston valve Dwill be moving to the left in Fig. 1, so as te admit vapor .from thevapor space 4 via the port 3 to the neck d of the valveD, and after thevapor iscut off by'a reverse movement of the piston-valve D', and theport 5 and exhaust-'port 6 have been opened so as to register vwith theneck d of the valve D', the exhaust vapor will escape via the neck d ofthe valve D through ort 5 into Lexhaust -vapor space 6, and the ex austvapor checkindicated by the arrow in Fig. 2, and adlnitted by thehand-controlled air intake valve V"l into the mixer V", the exhaustvapor, together with .the atmospheric air, will be carrieddown throughthe pipe U and the check-valve V4 into 1the crank-box chamber. I 4

N N2 so as to filLthe entire space on the crank-side of the piston B andcrank-box chamber N N2 at-Lwhatever pressure the ail:v

intake -puppet valve o will admit of, according to the tension of litssprings and 'v'ariations of the same by the actionof the tappet t andthe lever f in the stroke of the tappet-rod P, which in any event mustbe less than atmospheric pressure. I

At the time the exhaust is just commencing to take place the smallcylinder A, the piston a will be at the bottom of its outward stroke,and the piston B will be at the top or at the end of its inward stroke,by which time its upward displacement within the cylinder B shall havereduced the pressure in the crank-box chamber N ',N2 sufliciently totake in a quantity of air through the intake puppet valve fu from thesurrounding atmosphere into the crank-box chamberN N 2 together with theVexhaust vapor from the expansive portion,

as already explamed; and as the piston B is descending it will compressthe mixture which was drawn into the crank-box cham- 'ber N N2. lhemixture of vapor and air contained within the crank-box chamber N N 2 atthis time is incomplete, the quantity of air contained in the mixturebeing less by the amount of air by volume which the iston B displacesduring its stroke than the quantity of air necessary for the best proportions of air and va or, for an explosive mixture thereby obviatlng toa great extent the liability of back tiring from the combustion chamberB into the crank-box cham- The mixture Vcontained in the crank-boxchamber N N2 however, when `insutiiciently mixed as stated withatmospheric air, is mixed with sufficient of the latter to render thesame slowly combustible but unexplosive. The remaining quantity of airrequisite to form the explosive mixture, is contained in that spacewithin the cylinder B above the piston B', which has been left over bythe scavengering opera.- tion and is suliciently below atmosphericpressure when the piston B" is at the limit of its outward or workingstroke to admit of the char e from the crank-box chamber N N2 wit outhavin the total pressure in the combustion chamer B after the mixture-therein is com lete, greater than that of the.

atmosphere. -n` fact, as will be hereinafter explained, the pressureofthe completed mixture within t-he combustion chamber B should be lessthan that of the atmosphere by the amount which the piston B displaceswhen the same is moving upwardly and the port 9 has moved to a positionto overrun the port 8 after which time compression of the mixture in thecombustion chamber B may commence.V Conversely upon the downwardmovement of the piston B the incomplete mixture withheld in thecrank-boxchamber N N2 should be sufficiently lower in pressure than that of theatmosphere to etl'ect a balance in the pressure of the combustionchamber B after the transfer of the fuel from the former which willbring the pressure in the chamber B- to the required degree. At the timewhen the piston B is descending the .small piston a forcing the exhaustall the ing devices before mentioned and pipe U' and check-valve V4 intothe crank-box chamber N N2, andby the time the piston B has arrived atthe position shown 1n Fig. 1, or at the end of its stroke, the port (5will register with the port 6", allowing the incomplete mixture whichhas been partly formed in the crank-box chamber N N2 to escape. by itsown pressure resulting from the compression given to it by the )iston B,into the upper part of the cylinder B, through the connecting-pipe v andbackpressure check-valve lv, and perforated plate y'. The ellect of thepassage of the mixture through the small perforations 14, in the plate Jis to induce a more thorough mixing of the incoming lcharge with the aircontained inthe cylinder B, which toffether with the incoming cha rge,completes tie explosive mixture prior to compression and ignition.

When the piston B has reached the up per limit of its inward orcompression stroke,.indicated by a dotted line extending across thecylinder B, (Fig. l), the explo- Vsive mixture will be ignited by theelectrical ignition plu O actuated by the tappet t secured to 51etappct-rod P, as aforesaid; and the piston B will make its First outwardworking stroke by the expansion of the combustiblc gases contained inthe cylinder B. When the piston B has almostcompleted its outwardworking-stroke so that its port 9 will register with the exhaust-port 8,the gases resulting from combustion will exhaust through the port i),exhaust-port 8, exhaust drum 9, exhaust outlet 9 (shown in Figs. 5 and9) into the atmos here. In the meanwhile the piston a has een making itsinward stroke and creating a partial vacuum in .the cylinder A. Upon afurther outward movement of the piston B so that the piston-port 9 willregister with the scavenger port 10, and the trunkcd extension or pistona is moving,r farther in its inward stroke, and when the scavengerinfrpiston-port 8 will also register with the nort 10, atmospheric air willbe drawn into the exhausting. scavengering cylinder A', through thevalve /L of the threeway cock H and through the air-pipe 17, check-valvet6, air passages 15, air space J', perforations 14, piston-port9,.scavengering port 10, scavengering check-valve 10', (shown in Figs.'and 9), and scavenger-ing-piston-port l8, thereby creating anatmospheric shower in the cylinder B of a sufficient quantity of air todisplace ,the residual of theexhaust contained within the cylinder B andsupply that volume lacking in the scavenvermg cylinder A", bytransferring the residiial of the exhaust from the cylinder B into thesc-avengering cylinder A. When 'the 'piston B has moved downwardly inits working stroke so that the piston port 9 registers with the port 8,the pressure of the products of combustion in the cylinder B will,.after they have made their escape by means yof the exhaust drum 9 -tolthe atmosphere, be at atmospheric pressure, but when the piston hasmoved farther in the same direction so that the port 9 registers withthe port 10, the exhaust port f8 will have been Ycut oli' and thepressure contained Within the cylinder B will now .be slightly less thanatmospheric pressure. Axt this instant,

' however, 'the scavengering piston .a pumps the products vof combustionfrom the cylinder B into the cylinder A,l and draws after it -the chargeVof sca-ven ering air through the intake valve 16 as a oresaid,whereupon the atmospheric pressure of the cylinder B will have beenIconsiderably reducedfbelow that of atmospheric pressure dependinghowever on the degree of vacuum in the cylinder A', and the resistance.of :the check-valve 16. `In practice I have made the displacement -ofthe piston a somewhat in excess of that lof the piston B, so as to allowfor' varyin displacements oair drawn into the cylinder B by the varyingAtension of the scavengering intake check-valve 16. rfIhe resultattained by this means of scavengering the cylinder B of the residual ofthe exhaust and carry-ing lit into the exhaust or. scavengering cylinderA is an e'fect'ualclearing out of the `smoke and roducts of the previouscombustion .left aliter the exhaust has 'taken place, leaving thecylinder B with a clean supply oft atmospheric air with which to mix itsnew incoming charge ot' air and vapor and lat 4the same time facilitiesare .afforded by the piston a for varying the quantity of residual aircontainedfwithin the cylinder B after scavengering whereby the totalmix-ture of air and mixed fuel to the crank case and entering'thecylinder B prior to compression may be varied, admitting of variationsin the compression of the mixture prior to ignition, which when desiredmay be of high value when .employing a mixture ,containing less air andmore fuel and by virtue of jhe corresponding temperature, due to the'lexcessive compression it may be ignited as readily as a mixturecontaining a greater .quantity of airat a lower compression.

I consider these features-of my invention of considerable importance-and of considerable advantage in eiici'ency in explosive engines .andboth of thesefeatures I consider of a distinct advantage in internal.com-bustion motors. p

Upon-the downward movement of the piston a. the scavengered gases in thecylinder A will be forced on to the top of the piston a through thecheck-valve 2, and upon the upward movement of the piston a', the scav--engered gases in the `scavengering cyilinder A Will lbe itorce'd outthrough the checkvalve 2 (see Figs. 5 and 9) inte the ex haast outlet 9and into the -atmosphere, thus providin for the cylinder B a second orresidual ex' aust.

It. will be noticed. by studying the movement of the piston B and theplston a that .after the exnllosive'mixture has been taken into .thecylinder iB :on the top of the piston B, and fthe piston B is movingupward .and about to make its' inward or comp-ression stroke that someof the 5explosive mixture would be pushed out through the niston-port 9and. -scavengersport lo, piston scavengerifng-port 28" and into 'theexhaust -or `scavengerifng cylinder A". This fis prevented byAscavengerin-g port check-valve 1'0l interrupting .the vcontinuity ofthe port 119, which valve is shown in Figs. 6 and 9. oliice of this.check-valve 'is to mevexrt fthe escape of the explosive mixture 'fromcylinder B into the scavengering cylinder A when 4'the quantity ofexplosive .mixture in 'the cylinder .-B, is above its intake pressure,when slightly compressedb. .the piston B when making that portion o itsinward stroke, :to bring the piston-,port 9 into regrising 'offthecheck-va ve 10 therefore depends upon the degree of com' ressioncontained in the scavengering cylinder A as compared with the'compressi-on ofthe explosive .mix-

ture contained in the cylinder B. That'is to say,rduring the upwardstroke of the plston' B nj .the downward stroke of the 4.piston a', thcompression of the medium yor ygases contained in :the fsoavengeringcylinderv A must bein excessof the ressure of theiexplosive mixturecontaine in the cylinder @13,

so that the check-valve 10 will '.b seated by vthe -r excess ofthepressureof the -burnt gases contained in- .scavengering cylinder A.. Inorder to y create this -excesslve :amount of pressure :the cylinder-wilat .the time of the registration ofathefconmunicating ports from'thecylinder B vto'the-cylinder A', as

.already stated, check-:valve 2 must -;be .-ad-

justed by the :tension spring :shown 1the drawings, which can be donebyscrewing up .ter with the scavengering portl'O. The seat-s` 95 the nut-on .the end off the check-so aslto ,pnt

more or less compression .upon the spring. Access to the check -va-lve'may be had through -.the hand-hole--covered by the plate Qshown inFigs. I8 and 9, which, incr-der to make ,gas-tight, :is arranged to open:ontwardly from the crank-box chamber-N -z'N with suitable fbolts and:nu-ts` and :a gasket. A similar hand-hole Q', is'arra-nged inithe,crank-box chamber vr-N N2 but opening wardly. The object -of freversmgthe-manner ofclosing these'hand-ho'l'es is tombo'vde `for a bettersealing-ott' of the-gassoso!` :at-

mospheric air from, on the onehand, enterthe other hand, for preventingthe escape of the charge for the cylinder B under pres- Athe cyhnder Aafter the port 8 .back pressure from cylinder sNurlI contained in thecrank-box chamber It is desirable in order to obviate undue work imposedupon the engine during the creating of the vacuum in the cylinder A toarrange a compensating pressure device which will remove a portion ofthe load on the upper side of the .piston a during the exhausting periodof the same, and to this end l have preferred to provide for thetransfer of the scavengering' exhaust by compressing the contents of thecylinder A suiiiciently to lift the check-valve 2. This, however,depends upon, the pressure, on the other side of the' iston a which I'control by check-valve 10 the adjustment of which is under the influenceofthe engine. To this end I have arranged to release the scavengeredgases held under pressure in has-passed downwardly beyond port 10. Thisgives a little vacuum above the piston a with which to force thecheck-valve 2 open. It must be remembered that the port 10 is controlledby a check-valve 10 which prevents any A against cylinder B and permitsonly of transmission of the contents of cylinder B into cylinder A.Therefore when the piston B has moved to a position so that the pistonport 9 registers with the port 10 on an outward or working stroke, andthe piston A is pumping or scavengering the contents of c lmder B', andupon further movement of t e iston B to the end of its stroke, there woud be considerable compression 1n the clearance space above the piston awhich would have to overcome the seating pressure due to gravitation ofthe check-valve 10". During this period the tappct T of the tap et-leverT is operated by the engine as 1 lustrated in Fig. 9 (in which figurethe crank centers are as illustrated in Fig. 1) permitting the freeescape of the ases under compression above the piston a t rough the ipe93, exhaust pipe 94 into the atmosphere.

on a further lnward stroke of the piston B and a downward stroke of thepiston port 8 will register with the port-10 and the port 9 will againregister with this port. It must be remembered however, that since thepressure of the charge in the cylinder B is less than atmosphericpressure, no transfer of the gases or fuel will result from cylinder Bto cylinder A since no pressure will be imposed upon the check-valve 1.0

interru ting the passage 10, but on the contrary t e piston a will bemaking a compression stroke on the scavengered gases contained incylinder A which ressure will depend upon the strength of t e spring ofthe valve which will assist in holding the check-valve 10 closed. Andafter the port 10, the check-valve 10 may be release by the tappet Tsince it is desired to create a partial vacuum above the piston a inorder to ermit of the comparatively unresisted rus of the gases from thecylinder A. through the check-valve 2 to the other side or head of thepiston a and for this reason the check valve 10 must be closed. After ithas been closed by gravitation, it will remain closed by the atmospherlcpressure until the gases in cylinder A shall have passed the check-valve2 and have entered the cylinder A on the other side or head of thepiston a. This will be when the pistou a is at the terminus of itsoutward stroke excepting, however, for the slight excess of pressure inthe cylinder A due to the resistance which the s ring offers to theopening of the check-va ve 2. On the next upward stroke of the pistona', and the next downwardstroke ofthe piston B', a artial vacuum will beformed in the c linger A as aforesaid and compression an( expulsion ofthe gases on the opposite side of the piston a will result; and in orderto relieve the piston a of undue work, in expelling the scavengeringgases through the check valve 10 to the atmosphere as aforesaid the tapet T will again open the valve 10 and tie same will remain open untilthe piston a again returns and passes the port 10. The amount of bac-kressure imposed upon the piston a', exerte principally etween the headof the piston a an the head .of the cylinder A', may be varied bypermitting a more free escape of the scavengered gases through thecheck-valve 10 by adjustln the stroke of the tap/pet T by shifting it-onthe tappet lever T that is to say the escape of the "ases undercompression between the heat of the cylinder A and the piston a may becontrolled by varying the stroke of the valve 10 (throttling the same toa greater or lesser extent).

The adjustments of the valve in the control of the working pressure ofthe combustible mixture, prior to Nignition as just described, providesfor a two cycle engine of the character under consideration, that. is anexplosive internal combustion inotor, a means for reventing the escapeof the fuel during t e period when the en ine is exhausting the escapeof which has een a fault in two cycle motors hitherto and pre' pression.

in combustion motors of the four cycle type,

it has been the custom to throttle the mix-- ture on light loads whichduring inhalation leaves the pressure of the combustible ingredients inthe cylinder less than that of the surrounding atmosphere prior to comIt would therefore appeal' that under continued throttling conditions,my two cycle combustion motor just described would for the same speedand power-output be excessive in size and consequently cumbersome. This,however, is. not the case slnce the clearance space above the piston head in cylinder B, indicated by the dotted line, 1s qulte small whichenables the final compression of the mixture to be pushed to as high adegree as possible which in practice I prefer to make 120 pounds, thusincreasing very materially .the initial piston pressure and 1nconsequence of the corref spending increased expansion of the gases,

after ignition, the mean effective pressure' upon the piston B may bemade even as greater greater than were the inducted charge 1n thecylinder B taken in at atmospherlc pressure or in other words were thecolumn taken into the cylinder B at the in- 1t1al `stroke'of the pistonB equal to the capacity of the cylinder B at atmospheric pressure.

1t is not usually possible to reach a high range in adiabaticcompression since spontaneous ignition frequentlyioccprs due to anoverheated cylinder or pistonf'th temperature of which is difficult tomaintain at a constant value. By my improved method of eyaporating theliquid fuel from the eXterlorV of the cylinder walls, a much bettercooling effect lmay be obtained than by the heating of water totheboiling point as has been customary in jacketed motors or those to whichmy invention relates. Furthermore in consequence of the facilities tovary the mixture for the Acylinder B by the amount of air delivered toit by the scavenger-lng piston a and the air taken in through the crankcase` by the valve V, I am enabled to reach a higher degree ofcompression in the cylinder B without preignition resulting than ininternalicombustion engines in vogue, and hitherto andprevious` to myinvention, thusA by providing a compression of 120 pounds per squareinch, it will be necessary to adjust the tension` on the spring 2,".andthe check valve 2, and the intake air valve V, and the tension spring b,

so as to admit less atmospheric air to the cylinder B by thescavengering piston a.

by the evaporation of a volatileliquid; a

greater transfer of heat units per second may be effected than byradiation at a corresponding temperature; thus the control ot' thecylinder temperature may be more closely guarded than by the methods ofcooling hitherto and previous to my invention of which I am aware,thereby enabling me to compress the combustible charge in the cylinder'B, prior to ignition, t-o a higher degree than by the usualwater-(voided type of internal combustion motor; thus maintaining alarge power-output lfor a given fuel consumption and crank shaft speedof the motor than would otherwise be possible. The check valve 10 isoperated by a tappet T which is operated in turn by a connecting-leverT, and pump piston-rod' L', as more clearly illustrated in Figs. 5 and9.

The check-valve` 10 is connected up, as

shown in Fig. 9, ywith the outlet 9"', a small portion of which is shownin section. at the top of the scavengering cylinder A inFlg.

1, and which is also shown in the sectional l view of the valve 10 inFig. 9 in the interior of its chamber, in a manner so that the exit ofthe gases contained above the/piston a will be under the check into thedome of the valve, thence by an outlet-pipe' (shown broken away in Fig.9 for convenience of illustration) into the outlet of the exhaust valve2. The stroke given to the lever "1" by the pump piston-rod L is such asto synchronize with the downward movement ofthe piston a', and theadjustment of. the -tappet T. on the connecting-lever T must be inamanner which will give the lifting lever ofthe check-valve l thatamount of stroke which will lift the valve off of its seat, equal to thetravel of the piston a. downward from the position which it'occupiesfasshown in Fig. 1, until the port 8 in 'the piston shall have just passedand closed the scavengerino'` port 10, after which time the tappet Twill no longer contact with the lifting-lever of the check-valve 10,whereupon the check-valve 10 will close by gravity and will remainclosed until a suiiicient fallin the pressure of the gases which havebeen transferred from the cvlinder A through the check-valve 2 to thetop of the piston a has taken place.

It will be observed in Fig. l, that' the clearance between the top -partof the piston i a and the adjacent end of the cylinder A is quite small,and that upon a small amount of displacement of the piston a in adownward direction, a great reduction in the pres-l 'inder A will beeffective, notwithstanding the increased tension of the spring seatingof the check-valve 2; and upon the upward movement of the scavengering-piston a, the gases contained in the clearance space before mentionedor that space on top of the piston a', will be ejected through thecheckvalve, l0 and the outlet of the exhaust valve 2 into theatmosphere. By this arrangement, I am enabled to keep the scavengeringport check-valve l0 seated by settin up a counteracting pressure in thecylin er A through the instrumentality ofl the' check-valve 10 and itsconnecting-gear, for a small part of the stroke of the piston a, andthen suddenly releasing this pressure during the remainder of itsstroke. To adjust the time of the release of this excessive pressureinthe scavengering cylinder A', I have employed an arrangement for thetappet T on the lever T, so that the checkvalve 10 may be opened for alonger or shorter period of time during the stroke of lwhich is adjustedfor a the scavengering piston a. As the piston B is moving farther inits compression stroke so as to bring its port 9 into register withexhaust port 8, there would be a .further tendency of the piston B toforce .the explosive mixture out of the' exhaust-port 8 and into theatmosphere, but to prevent this, I have introduced the exhaust checkvalve 2', back-pressure e ual to the maximum back-pressure develope bythel compression; of the explosive mixture when the piston isydisplacing that amount of volume/between the position of the port 9 inthe piston shown in Fig. 1, and that position which the port 9 occupieswhen registerin withthe exhaust port 8. That is to say, uring thisfraction of its compression stroke I accomplish this by Weighting thevalve 2 to the maximum amount of back pressure, and maintaining theadjustment at that weight, the valve closing by gravity. It will befurther noticed by inspecting`Fig. 1, that the joint ca a'city of thescavengering cylinder A an crank box chamber N N2 will be less than thatof. the crank-box chamber N N2, though the diameter of the scavengeringpiston a is greater than that of the piston B as hereinafterstated. The

4area of the upper side of the scavengerin piston A, or that side ofthesaid piston use for forcing out the residual of the products ofcombustion into the atmosphere should be equal to the area of the pistonB', 4and the suction created in the cylinder A and crank-box chamber NN2 by the action of the scavengering piston a' should b`e greater thanthe compression in the space below'the piston B in the crank-box chamberN N2. -In other words, the negative pressure of the crank-box cham- N2should be greater at its maximum than the positive pressure in thecrank-box chamber N N2-at its maximum.

When it is desired to till the cylinder B .aint

with its charge having a pressure balancing that of the atmosphere orbelow that of the atmosphere prior to compression, the change of theexplosive mixture being made up of air which is the residual of theatmospheric shower or scavengering charge as well as the air and vaportaken into the crank-box chamber N N2 at the intake, and afterward fedby compression by the downward stroke of the piston B into the cylinderB from the crank-box chamber N N2, the volume contained in the cylinderB and the volume taken into the cylinder B from thecrankbox chamber N N2would both be below atmospheric ressure. This diminution in the pressureo the respective volumes in the cylinder B and the crank-box chamber NN2 is due to the resistance of the scavengering check-valve 16 and t-heintake valve o to the incoming columns being greater than that necessaryto balance atmospheric presy sure. In adjusting thefmotor so as tooperate by an explosive mixture in the cylinder B at or aboutatmospheric pressure, as aforesaid, considerable tension will berequired upon the check-valve 16 and the valve springs must be soadjusted that the residual of the atmospheric'shower left in thec'ylinder B will be considerably below atmospheric pressure in orderthat the cylinder B will be in a condition to receive the additionalincoming charge from the crank-box chamber N N2, which, in consequenceof being under pressure will be up to or above atmospheric pressure. Itis thereforeobvious that in order to perfectly displace the residual ofthe roducts of combustion after exhaust, by thepiston a whenthe pressureof the residual of the atmospheric shower in the cylinder B is less thant iat of thefatmosphere, as aforesaid, the difference du|` to thiscontraction in the quantity of the air contained in the cylinder B mustbe made u" by the displacement of the piston lib cylinder A; and in'makink up this difference by the dis lacement o the piston c in l thecylinder i5, the amount of compression of the gases in the crank-boxchamber N N2 by the downward movement of the piston B must beconsidered. It is therefore obvious that the exhaustion of thescavengering cylinder A must have a greater negative value than thecompression in the crank-box chamber N N2 by the piston B. I havetherefore preferred to not only increase the area of the scavengeringpiston a so as to provide for a surplus `ume of air and exp escape 'ofthe exhausted 'gases 'when 'there .is

the volume of explosive mixture in the cylinder considerably belowatmospheric pressure when the piston is at the limit of its loutwardstroke pri-or to compression, so that the compression may be carried upto almost as great a pressure as the initial piston pressure whenignition takes place,v and vhave considerable room left in the cylinderwhile impelling the piston forward in its 'work mg stroke for a longexpansion of the ases `when' performmg the mechanical wor of the engine.It is this thermodynamic considerationwhich I have 'reference to indescribing the relative capacities of the cylinder A and crank-boxchamber N N2 and the underneath side of the piston B and' crank-boxchamber N'N2 commensurate with obtammg a complete scavengering veffectof the cylinder B, to ether with a good margin for expansion of t ecombustible mixture in the motor.

the cylinder B after ignition. o

By the manner of adjustment whereby I am enabled to vary automaticallythe volosive mixture taken into the cylinder B, I am enabled to operatemy motor on fluctuating loads and mean loads with a high degree ofeconomy from a thermodynannc standpoint; and on overloadsv when themotor is-operating beyond its normal rated capacity the means for varyinthe supply of fuel taken into the cylinder is such that the `volume ofgas contained within the cylinderB may be` considerably in excess ofthat of the atmosphere before compression. In fact, it may be all ofthat in excess of what the piston B displaces when -it is making itsdownward stroke with all of the tension taken oil of the intake valve,as before explained,` so vas to admit of the air being taken into thecrank-box chamber N N2 atvery nearly atmospheric pressure prior to thedownward displacement of the piston B. During the operation of theengine and at the time when the valve D shall have moved into a positionfor release so as to open Ithe exhaust-port, and the piston a is at theend of its inward stroke. the piston B will be at its upper or com'-pression stroke, at which time the suction created inthe crank-boxchamber- N N2 by the upward displacement of vthe piston B will be suchas to'irst draw in the exhausted.

gases from the exhaust-space 6 of the expansive section through thevapor-exhaust check-valve V prior to the mtake of yair from 'theatmosphere through the air intake fcheck-valve fv'" by 'of the tensionof the springss and s seatmg the sald vulve, the

'air .having to work against the'resistance of the said springs. vTheeffect will be to effectually exhaust 'the vapor from the exhaust-space6 after the manner of a vacuum. pump so as -to leave the exhaustpressure l.in the 'va-por cylinder A vat that time below at- 'mosphericpressure, after which the exhaust plus the weight of the smalcheck-valve V, and the slight compression due to the downmerely thatagainst4 atmos heric pressure Ward movement of the piston Bl when atlabout three-quarters of itsstroke. By this time, the piston-valve D willhave closed the exhaust port so as 'to cut oi .the exhaust and preventany further back-pressure'from the com re'ssion vdueto the'downwardmovement o1 thepiston B. Of Icourse 'this depends u on the lap andleadof the siideval-'ve D in its travel, which is varied in accordancewith the speed 'of -the shaftovernor during the variations in the speeof Vhen employing the commercial 'naphtha for 'operating 'mythermodynamic motor, the quantity of vapor necessary for the fuel forthe explosive ortion maybe varied 'at will by varying tige pressurecontained in the jacket 1. In the eventof the naphtha vapor being inexcess of that required 'for lthe 'exploslve lcylinder to 'constitutethe lbest proportion or the explosive mixture, 'the 1nxtial pressure maybe increased in the jacket I, and the valve D adjusted so las 'to 'cutoff earlier in its stroke, or the vapor may be throttle'd bythethrottle-valve M; land in the event of a deficiency occurring in theuantit o'f the naphtha vapor rejected by t e cylmder A for propercombustion in the lSL00 into a position so as .to turn oif the supplyof, air which, as previously stated,'wa's drawn through the cock H,supply-pipe 17 and check-valve 16; and by turning the valve h into aposition so that the port h 'will reg'- -ister with the smoke-fine 13,communication of 't-hepipe 17 with the smoke-iluel will beestablishedby* the cock H, and the supply of air to the cylinder B wilt be taken 1nthrough the :tempering iiues 11, smoke-flue th'einterior of the cylinderand is added to the explosive mixture, and in case of the moval oftheliquid in the jacket I, I employ a drain-cock R having a passage-way(shownj 4which is continuously drawn in through the l I so as to reducethe working pressure of the tempering fines will take up the excessiveheat of the naplitlia contained in the jacket vapor. Of coursetliis heat1s also taken into heat being still excessive so as to produce too greata pressure, the cock H can be manipulated so as to allow some cold airto enter through the check-valve 16 as well as heated fair through thetempering flues `11. The amount of air taken in through the intakescavengering check-valve 16 as already stated, is varied by thevariations in the compression of its spiral compression sprin s.

In arge engines of this class,when it 1s not practical to lubricate theinterior of the cylinder in the manner before stated, I einployindependent lubricating 'devices in the ordinary way for lubricating thecylinders' of gas engines. In order to permit of the rein dotted linesin Fig. l) in the casting of the cylinder B at the lower end. A similarcock R (shown in Fig. Al) is employed forv the vapor jacket A.

In making use of the-term explosive en-I gine throughout thisspecification, I meanf those engines in which the fuel is burned behindthe piston within the working cyl-i inder, and therefore the term hasreferencel to a variety of engines of the slow combustion type in whichthe fuel is fed in more or less gradually and consumed behind theworking piston; and, as I do not wish to confine my invention to eitherrapid or slow combustion engines, I wish to make myself explicit in thisrespect, that'in using the term explosive engine IJ mean those eninesknown in the trade as the internal comustion ty e as well as thosecommonly known as t e explosive type, as the principle of my inventionmay be employed with either the slow or rapid combustion types ofengine-without departing in the least from its spirit. i Although I havedescribed my invention in thermodynamic motors using an expansiveportion of about 11.12 per cent. of the cylinder capacity of theexplosive ortion, I do not desire to limit myself to tiiese proportionsin reducing my invention to practice. I have considered, however, that aart of the forty per cent. of heat'wasted or inarily in explosiveengines could be bestused in a simple manner by carryin. out pro ortionsof about those specified. bviouslyii using a greater quantity of thevolatile liquid than that which could be used as fuel for the exmaaarplosive portion, a greater portion of the forty per cent. could beutilized, and the exansive portion could therefore bc made arger, but anadditional cooling agentwould have to be employed to reduce thetempera-- ture of a reater part of thevapor after the same has eenrejected by the expansive ortion. As the quantity of naphtha containedin the expansive vapor would have to be reduced so as to meet therequirements demanded for the best chemical conditions for operating theexplosive portion, this would mean that the vapor would have to be putthrough a ump and condenser and brought back to a iquid state, andreturned by the pum to the jacket I to be used over again, whic wouldintroduce objectionable features in the operation of the `4engine from acommercial stand-point; and in conse uence I have confined myself in thedescription to what I considered th'em'ost simple method of operating athermodynamic motor on the expansive and explosive principle, byeinploying only one liquid for the fuel, the power medium and therefrigerator for the ex losive portion.

I have throughout this specification occasionally referred to myimproved motor as being divided into two portions, terming one of thesethe explosive portion and the other the expansive portion. I mean toinfer by this that a portion of the motor is o Jerated directly by theexplosive power of t ie coin-N bustible ingredients, and another portionof the motor is operated indirectly by thehcat thereof and through theexpansion of a medium which takes up the heat through the heated partsof the motoi' with which the same is i'n contact during theconflagration or combustion of the fuel. I therefore desire to interpretthe explosive portion of the engine as that portion lyin to the ri ht ofthe dotted line 9 as indicate in Fig. 1, and the expansive portion asthat portion lying to the left of ythe said dotted line.

I will hereinafter occasionally refer to the expansive portion thusinterpreted as that of a thermodynamic transformer in which the heat istransformed into work by the indirect process, since the significance issimilar in this sense to the application of heat in the vaporization ofwater in order to operate a steam engine, and to the ex losive portionthus interpreted as a thermo ynamic transformer wherein the heat istransformed into Y process. By the primary thermodynamic process I meanthe direct application of heat into mechanical work as is exemplified-inthe explosive portion of' m improved motor wherein the expansion o thegasesresulting from combustion-acts directly as upon the thermodynamictranslating instrumentalities, that is thepiston B. and the crank andconnecting rod co-actin therewith; and by the secondary thermoynamicprocess I mean the indirect application of heat into mechanical work asis exemplified 'in the expansive portion of my improved motor whereinthe expansive power medium as previously referred to derives its energyin expanding behind the thermodynamic translating element, as forexample the piston a in the driving of the connecting rod I Aand crank cin the performance of mechanical work. v

Ishall occasionally refer to the transfer of heat into mechanical motionor Workas that of a thermodynamic transformation, and shall refer ingeneral to thepiston and cylinder or the pistons and cylinders and theircranks andconnecting rod as thermodynamic transforming elements.' p

I am aware that previous to my invention expansive and explosive engineshave been sof-combined that the expansive engine was employed as astarting device for theexplosive engine. I am also aware that steamengines and gas engines, so-called, have been combined so as to workupon the same crankshaft. I do not claim these features as my invention.

'I do claim however, and desire to secure by Letters Patent of theUnitedStates 1 'The combination of an explosive engine, a liquid fuel supplyexposed to the heat of the cylinder of said engine, an expansion en-`.gine connected tosaid supplyl lto be driven by the vapor developedfromsaid fuel, and connections leading the exhaust of the expansionengine to'tl'iejcharge inlet of the-explosive engine.

2i In a thermodynamic motor, a combus tion and expansion chamber, aliquid fuel receptacle, a combustibleliquid power medium in contact withthe combustion chamber carried by the said receptacle adapted to operatethe motor by the vaporization thereof through-the transfer of heat fromthe combustion chamber, a connection between the said receptacle andtheexpansion chamber, means for controlling the admission and cut-oifof thevapor in the expenditure of the energy thereof within the said expansionchamber in the performance of mechanical work and for controllingthevexhaust thereof, together with means for4 coniiagrating a lofmechanical work.

.quantity of the spent vapor within the combustion chamber in thefurther performance 3. In a heat engine, the combination f. an explosioncylinder having a fuelsupply receptacle in contact therewith, the fueltherefor adapted to be heated by a surplus of the expansion cylinder,pistons with-in each of the cylinders, the piston within the expansioncylinder heated vby the surplus heat of the explosion cylinder, aconnection between the two cyl- 'inders for permitting the transfer ofthe said heated fuel, and a valve and valve-gear for controlling theexhaust of the expansion cylinder into the explosion cylinder.

4. Ina heat engine, the combination of an explosive engine and a fuelsupply receptacle therefor, the same being adapted to contain a quantityof fuel and subject the same to the heat of the cylinder, and anexpansion cylinder adapted to receive said heated fuel and wherein thesame is adapted to expand in the cylinder heat of the explosioncylinder, an

being operated by the fuell further operation of the motor, theexplosive cylinder having a greater piston area than the expansioncylinder, a connection between the exhaust of the expansion cylinder andthe charge inlet of the explosive cylinder, for permitting the escape ofthe exinlet ofthe explosive cylinder.

5. In a heat engine, the combination of an explosive engine having afuel supply receptacle carried by its cylinder and adapted to thereof,and an expansion cylinder co-acting' with the explosive engine andoperated by the expansion of the heated fuel, a connection between theexhaust of the expanpass' regulator and suitable pipe connectionthereforfor controllingv the heating effect of the flues.

7. In an explosive engine having a vapor generator 'heated Aby a surplusofthe cylindeifheat of the explosive engine, and an auxiliary expansiveheat engine deriving its energy from. the sensible heat of the vapor ofthe said vapor generator,'the combination of `an independent heater forthe said vapor generator having hot-air flues therefor, and of a valveand cold air pipe for the subject the same to the .action of the heat."

haust of the expansion chamber to the charge lsion cylinder and thecharge inlet of the ios tion of -a vapor generator heated by a sur-g'

